📄 smc.c
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/*************************************************************************/
/* */
/* Copyright (c) 1993-2001 Accelerated Technology, Inc. */
/* */
/* PROPRIETARY RIGHTS of Accelerated Technology are involved in the */
/* subject matter of this material. All manufacturing, reproduction, */
/* use, and sales rights pertaining to this subject matter are governed */
/* by the license agreement. The recipient of this software implicitly */
/* accepts the terms of the license. */
/* */
/*************************************************************************/
/*************************************************************************/
/* */
/* FILE NAME VERSION */
/* */
/* smc.c PLUS 1.13 */
/* */
/* COMPONENT */
/* */
/* SM - Semaphore Management */
/* */
/* DESCRIPTION */
/* */
/* This file contains the core routines for the Semaphore Management*/
/* component. */
/* */
/* AUTHOR */
/* */
/* Accelerated Technology, Inc. */
/* */
/* DATA STRUCTURES */
/* */
/* None */
/* */
/* FUNCTIONS */
/* */
/* SMC_Create_Semaphore Create a semaphore */
/* SMC_Delete_Semaphore Delete a semaphore */
/* SMC_Obtain_Semaphore Obtain instance of semaphore */
/* SMC_Release_Semaphore Release instance of semaphore*/
/* SMC_Cleanup Cleanup on timeout or a */
/* terminate condition */
/* */
/* DEPENDENCIES */
/* */
/* cs_extr.h Common Service functions */
/* tc_extr.h Thread Control functions */
/* sm_extr.h Semaphore functions */
/* hi_extr.h History functions */
/* */
/* HISTORY */
/* */
/* DATE REMARKS */
/* */
/* 03-01-1993 Created initial version 1.0 */
/* 04-19-1993 Verified version 1.0 */
/* 08-09-1993 Corrected pointer retrieval */
/* loop, resulting in version 1.0a */
/* 08-09-1993 Verified version 1.0a */
/* 03-01-1994 Moved non-core functions into */
/* supplemental files, changed */
/* function interfaces to match */
/* those in prototype, added */
/* register options, changed */
/* protection logic to reduce */
/* overhead, resulting in */
/* version 1.1 */
/* */
/* 03-18-1994 Verified version 1.1 */
/* 04-17-1996 updated to version 1.2 */
/* 03-24-1998 Released version 1.3 */
/* */
/*************************************************************************/
#define NU_SOURCE_FILE
#include "cs_extr.h" /* Common service functions */
#include "tc_extr.h" /* Thread control functions */
#include "sm_extr.h" /* Semaphore functions */
#include "hi_extr.h" /* History functions */
/* Define external inner-component global data references. */
extern CS_NODE *SMD_Created_Semaphores_List;
extern UNSIGNED SMD_Total_Semaphores;
extern TC_PROTECT SMD_List_Protect;
/* Define internal component function prototypes. */
VOID SMC_Cleanup(VOID *information);
/*************************************************************************/
/* */
/* FUNCTION */
/* */
/* SMC_Create_Semaphore */
/* */
/* DESCRIPTION */
/* */
/* This function creates a semaphore and then places it on the list */
/* of created semaphores. */
/* */
/* AUTHOR */
/* */
/* Accelerated Technology, Inc. */
/* */
/* CALLED BY */
/* */
/* Application */
/* SMCE_Create_Semaphore Error checking shell */
/* */
/* CALLS */
/* */
/* CSC_Place_On_List Add node to linked-list */
/* [HIC_Make_History_Entry] Make entry in history log */
/* [TCT_Check_Stack] Stack checking function */
/* TCT_Protect Data structure protect */
/* TCT_Unprotect Un-protect data structure */
/* */
/* INPUTS */
/* */
/* semaphore_ptr Semaphore control block ptr */
/* name Semaphore name */
/* initial_count Initial semaphore instance */
/* count */
/* suspend_type Suspension type */
/* */
/* OUTPUTS */
/* */
/* NU_SUCCESS */
/* */
/* HISTORY */
/* */
/* DATE REMARKS */
/* */
/* 03-01-1993 Created initial version 1.0 */
/* 04-19-1993 Verified version 1.0 */
/* 03-01-1994 Changed function interfaces to */
/* match those in prototype, */
/* added register options, */
/* resulting in version 1.1 */
/* */
/* 03-18-1994 Verified version 1.1 */
/* */
/*************************************************************************/
STATUS SMC_Create_Semaphore(NU_SEMAPHORE *semaphore_ptr, CHAR *name,
UNSIGNED initial_count, OPTION suspend_type)
{
R1 SM_SCB *semaphore; /* Semaphore control blk ptr */
INT i; /* Working index variable */
/* Move input semaphore pointer into internal pointer. */
semaphore = (SM_SCB *) semaphore_ptr;
#ifdef NU_ENABLE_STACK_CHECK
/* Call stack checking function to check for an overflow condition. */
TCT_Check_Stack();
#endif
#ifdef NU_ENABLE_HISTORY
/* Make an entry that corresponds to this function in the system history
log. */
HIC_Make_History_Entry(NU_CREATE_SEMAPHORE_ID, (UNSIGNED) semaphore,
(UNSIGNED) name, (UNSIGNED) initial_count);
#endif
/* First, clear the semaphore ID just in case it is an old Semaphore
Control Block. */
semaphore -> sm_id = 0;
/* Fill in the semaphore name. */
for (i = 0; i < NU_MAX_NAME; i++)
semaphore -> sm_name[i] = name[i];
/* Setup the initial semaphore instance count. */
semaphore -> sm_semaphore_count = initial_count;
/* Setup the semaphore suspension type. */
if (suspend_type == NU_FIFO)
/* FIFO suspension is selected, setup the flag accordingly. */
semaphore -> sm_fifo_suspend = NU_TRUE;
else
/* Priority suspension is selected. */
semaphore -> sm_fifo_suspend = NU_FALSE;
/* Clear the suspension list pointer. */
semaphore -> sm_suspension_list = NU_NULL;
/* Clear the number of tasks waiting on the semaphore counter. */
semaphore -> sm_tasks_waiting = 0;
/* Initialize link pointers. */
semaphore -> sm_created.cs_previous = NU_NULL;
semaphore -> sm_created.cs_next = NU_NULL;
/* Protect against access to the list of created semaphores. */
TCT_Protect(&SMD_List_Protect);
/* At this point the semaphore is completely built. The ID can now be
set and it can be linked into the created semaphore list. */
semaphore -> sm_id = SM_SEMAPHORE_ID;
/* Link the semaphore into the list of created semaphores and increment the
total number of semaphores in the system. */
CSC_Place_On_List(&SMD_Created_Semaphores_List,&(semaphore -> sm_created));
SMD_Total_Semaphores++;
#ifdef INCLUDE_PROVIEW
_RTProf_DumpSema(RT_PROF_CREATE_SEMAPHORE,semaphore, RT_PROF_OK);
#endif
/* Release protection against access to the list of created semaphores. */
TCT_Unprotect();
/* Return successful completion. */
return(NU_SUCCESS);
}
/*************************************************************************/
/* */
/* FUNCTION */
/* */
/* SMC_Delete_Semaphore */
/* */
/* DESCRIPTION */
/* */
/* This function deletes a semaphore and removes it from the list */
/* of created semaphores. All tasks suspended on the semaphore are */
/* resumed. Note that this function does not free the memory */
/* associated with the semaphore control block. */
/* */
/* AUTHOR */
/* */
/* Accelerated Technology, Inc. */
/* */
/* CALLED BY */
/* */
/* Application */
/* SMCE_Delete_Semaphore Error checking shell */
/* */
/* CALLS */
/* */
/* CSC_Remove_From_List Remove node from list */
/* [HIC_Make_History_Entry] Make entry in history log */
/* TCC_Resume_Task Resume a suspended task */
/* [TCT_Check_Stack] Stack checking function */
/* TCT_Control_To_System Transfer control to system */
/* TCT_Protect Protect created list */
/* TCT_Set_Current_Protect Modify current protection */
/* TCT_System_Protect Setup system protection */
/* TCT_System_Unprotect Release system protection */
/* TCT_Unprotect Release protection */
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